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Should GM improve the power cord and plug on the 120 volt Voltec Charger?

  • Yes. Mine gets hot! This needs to be fixed.

    Votes: 33 42.9%
  • No. It's fine.

    Votes: 44 57.1%
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Discussion Starter #1 (Edited by Moderator)
Voltec 120 volt charger cord.

Closing thread. It was already changed!! This is from 03-21-2012:
UPDATE:

Chevy agrees with ME! They finally have listened! Chevy has issued a replacement program with a NEW Charger Cord! The NEW cord is black 14 gage wire. The NEW NEMA plug is substantially better quality.

You can see a picture of it here:

http://gm-volt.com/forum/attachment.php?attachmentid=5101&d=1332372201

Thank you Chevrolet!

ORIGINAL POST
The 120 volt charger that comes standard with every new Volt has an undersized power cord. (Shame on you.) The wire gage on the 120 volt utility plug is #16. #16 is too small for this load. This wire gets too hot. It is not safe. Also the cheap brass molded power plug is subject to overheating & melting. We have already seen this in the news and I have experienced it my self. This cord arrangement might slip by with a brand new outlet and a cold ambient temperature but combine a warm day and a 10 year old outlet with normal aging corrosion and it's not safe. (I don't care if UL approved it or not... It is undersized for the load and it's not safe for the load you are placing on it.)

As a former IBEW electrician I am very disappointed with this cord. Since you sealed up the unit... the cord can't be replaced in the field by a qualified electrician.

Please increase the wire gage to #14 wire and use a better quality cadmium plated plug that is rated for 15 amps.

The Nissan Leaf charger comes with a superior power cord and they have not had any problems. (And the press has reported that too...)

GM does not need any more bad press about melting charger cords. Please don't ship any more units with undersized power cords & shoddy brass plug contacts.

Thank You.
 

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Maybe we can all email our VA's and let them know. It's a shame that the included EVSE is so low-rent compared to the rest of the car. But remember, the Leaf standard EVSE costs twice as much.
 

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As an engineer that designs electrical products #16 wire is just fine for the 12A load of the Volt EVSE. If the wire is getting hot its not due to the wire gauge but more likely to do with high contact resistance. It could be a poor plug or poor crimp connection.
 

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As an engineer that designs electrical products #16 wire is just fine for the 12A load of the Volt EVSE. If the wire is getting hot its not due to the wire gauge but more likely to do with high contact resistance. It could be a poor plug or poor crimp connection.
As a Volt owner who's already had not one, but TWO of them fail in the first 90 days of ownership.....
 

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As a Volt owner who's already had not one, but TWO of them fail in the first 90 days of ownership.....
Hey i'm not attesting to the Volt EVSE quality. I'm just saying don't blame the wire gauge. A 16 AWG wire will handle a 12A current no problem. There could be many other things that are causing the wires and plug to get hot.

A 16 AWG wire will dissipate about 0.6 W/ft of heat running at 12 A continuous. Not nearly enough to get hot.
 

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16 AWG is 4.016 milli-ohm per foot, at 12 amps equals a voltage drop of .049192 volts, but you have to account for the both conductors , so its 1.15 watts per foot of charger cord.

Also as the copper heats up, so does the loses, its about 0.4% per C, so a 30C rise will be 12% increase in resistance or about 1.3 watts per foot.

I'm and Engineer as well and while in free air, the heat/loss is manageable, the volt charger is designed to leave the wire coiled. One is looking at close to 30 watts of heat, if left coiled, and in my professional opinion is a safety hazard.

On my first charge, I left the most of the cable coiled and within 30 minutes the coiled wire was over 70C, which is at the UL limit.

Nissan uses 12 Gauge for a reason and I think the Volt 120V cord is a fire waiting to happen
 

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16 AWG is 4.016 milli-ohm per foot, at 12 amps equals a voltage drop of .049192 volts, but you have to account for the both conductors , so its 1.15 watts per foot of charger cord.

Also as the copper heats up, so does the loses, its about 0.4% per C, so a 30C rise will be 12% increase in resistance or about 1.3 watts per foot.

I'm and Engineer as well and while in free air, the heat/loss is manageable, the volt charger is designed to leave the wire coiled. One is looking at close to 30 watts of heat, if left coiled, and in my professional opinion is a safety hazard.

On my first charge, I left the most of the cable coiled and within 30 minutes the coiled wire was over 70C, which is at the UL limit.

Nissan uses 12 Gauge for a reason and I think the Volt 120V cord is a fire waiting to happen

Henry your calculations are correct (except that its a 4% increase in reistance not 12% as the resistance of copper is measured at 20C). i'm supprised that you would see a 40C temperature rise. I work in the heat tracing industry for products used in explosive gas environments so I do deal with temperature rise calculations all the time. Even with the cable completely coiled that 30W is still dissipated over a reasonable surface area. A standard sized 30W CFL light bulb might barely see a 40C temperature rise. I would think that something else would have to be wrong to see that high of a temperature rise.

We don't use 16 gauge for any of our products but I could go in to the lab and take a similar sized cable and run it at 1.2W/ft in a coil and measure the temperature rise when i'm back to work on Monday.
 

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I've had absolutely no problems with mine. The unit, the cord - neither even gets realy warm during charging.

I can't imagine what the problem is.
 

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Do we have any feedback yet on WHAT is failing in the charger cord unit ?

The first day any new Apple item is released someone has a complete take a apart posted (ifixit).

I have yet to see a simple block diagram - xray or circuit board picture posted here.

If Heathkit was still around we would see a Car charger kit :)
 

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Discussion Starter #10
As an engineer that designs electrical products #16 wire is just fine for the 12A load of the Volt EVSE. If the wire is getting hot its not due to the wire gauge but more likely to do with high contact resistance. It could be a poor plug or poor crimp connection.
No. I do not agree. The entire length of the cord gets warm (Not just the end.) and the plug contacts get very warm because of the thin gage of brass used. It is a very low caliber setup.
 

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Discussion Starter #11
I design electronic devices for a living too.,.. I need to be clear here. I am NOT talking about the 20 foot cord with the J1772 on the end. I am talking about the short 12 inch cord with the 15 amp NEMA wall plug. The molded NEMA connector is thin gage brass that gets very hot. (Warm enough to melt the molded vinyl plug body.) And the 12 inch cord gets hot along the entire length... Not just the end with the plug on the end.

Perhaps Chinese 16 gage wire is not actually good for 1250 watts? Perhaps the Chinese NEMA connector is not really good for 15 amps? Maybe the QC is just poor. But I do know that increasing the wire gage and from 16 to 14 gage would not increase the price more than a few pennies and using a heavier gage contact on the connector with cadmium plating would eliminate the issue.

As an electronic engineer and a former IBEW certified electrician... I say it again: Please use 14 gage wire and a decent quality cadmium plated plug on this charger. I don't like seeing the constant parade of pictures of melted Voltec chargers in the blogs & news every week. Just spend the extra nickel and do the right thing.
 

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Discussion Starter #12 (Edited)
We don't use 16 gauge for any of our products but I could go in to the lab and take a similar sized cable and run it at 1.2W/ft in a coil and measure the temperature rise when i'm back to work on Monday.
Your calculations assume that GM is using REAL 16 gage wire that conforms to actual 16 gage wire specifications...

It will not do any good measuring the temperature rise on a nice american grade of 16 gage wire. You need to measure the crappy chinese, low grade, rotten copper stuff GM is using on the Voltec unit. Otherwise all of your nice measurements & calculations mean nothing.
 

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Discussion Starter #13
As an engineer that designs electrical products #16 wire is just fine for the 12A load of the Volt EVSE. If the wire is getting hot its not due to the wire gauge but more likely to do with high contact resistance. It could be a poor plug or poor crimp connection.
You are assuming that the wire GM is using actually conforms to #16 gage AWG specifications. Maybe if GM was not using crappy, chinese, rotten copper wire that's missing a few strands (Because there is NO such thing as QC in China unless you go there your self and monitor production...) it might actually be good for 12 amps. Chinese 16 gage is like american 18 gage.

Spend an extra penny and use 14 gage.
 

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Hey i'm not claiming it's a good design. The 16 AWG wire with a 12 A load in the Volt EVSE will dissipate ~1.2W/ft and will get warm but should not get hot. The connector on the other hand is a whole different situation. A poor connector can be a huge problem and heat generated by the connector can conduct several feet down the cord (as copper is also a great heat conductor).

If i was designing the EVSE I would use 14AWG wire. From a cost standpoint there shouldn't be much difference as 14AWG is used more than 16 AWG wire.

On another note:
I don't own a Volt ... Yet. So I have only seen the connector first hand a few times. But I'm supprised they allow the use of the EVSE coiled. Most extension cords are not allowed to be used coiled and usually have a warning as such.
 

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Discussion Starter #15
So what do you think? Should GM improve the quality of the power cord on the standard 120 volt chager that comes with the Volt?
 

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You are assuming that the wire GM is using actually conforms to #16 gage AWG specifications. Maybe if GM was not using crappy, chinese, rotten copper wire that's missing a few strands (Because there is NO such thing as QC in China unless you go there your self and monitor production...) it might actually be good for 12 amps. Chinese 16 gage is like american 18 gage.

Spend an extra penny and use 14 gage.
Well we do buy some of our cord sets from China so I'm fully aware of some of the crap that comes out of there. But there are some suppliers in China that do know what they are doing. We have to work close with our suppliers to ensure good QC. I'm guessing that SPX does not have a lot of experience dealing with Chinese suppliers.

On a side note. GM does not make the Volt EVSE. SPX does. Edit : LEAR is the supplier not SPX. I was incorrect.
 

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How may times has it proved to be an old outlet and/or poor contacts? 9-10hrs at 1400kW is a lot. If your run your/a hair dryer in the same outlet for 9hrs does it's plug get hot. Ok, I realize you would not do that but it does make a point.

And, I do think (it is SPX not GM) they should put heavier wire and a heavy duty plug on it because the price difference is little. The MSRP is like $450 after all (if you buy a second one yourself).
 

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16 AWG wire should be fine for that load. Fulgrite is right though, 16 gauge Chinese wire is not the same as 16 gauge full spec wire. I haven't noticed it being warm though.
 

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For the price of the Volt EVSE LEAR should have put a 14/3 cable on it as the cost difference is likely less than a dollar. However it's common for 16/3 wires to be used up to 13A in extension cords. So the Volt cord is near the limit. As for the plug. A good plug is always needed. Especially for something like the Volt EVSE which will likely see many cycles and a reasonably long continuous use.
 

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16 AWG wire should be fine for that load. Fulgrite is right though, 16 gauge Chinese wire is not the same as 16 gauge full spec wire. I haven't noticed it being warm though.
Well to be fair China doesn't use the AWG wire standard in their country. They use the square mm system like in Europe. But a UL certifed 16 AWG wire in a cord set is usually made up of 26 strands of 30 AWG wire with a copper resistivity of 10.3 Ohms/circular mil. And the wires we buy from China meet this specification and are UL certified. China makes tonnes of wire. And there are plenty of companies that make quality wire in China for the North American market.

Mind you there are tonnes more in China that do make junk.
 
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